4C20.60 - Heat of Crystallization

Code Number:
4C20.60
Demo Title:
Heat of Crystallization
Condition:
Good
Principle:
Change of State
Area of Study:
Heat & Fluids
Equipment:
Re-HeaterTM Portable Heat Packs Containing Sodium Acetate.
Procedure:

The heat packs have an activating button.  Gently push on the button and the solution of sodium acetate will start to change to a solid.  As it does so it releases heat.

References:
  • B. Sandnes, "The Physics and the Chemistry of the Heat Pad", AJP, Vol. 76, #6, June 2008, p. 546.
  • Narayanan Menon, "A Simple Demonstration of a Metastable State", AJP, Vol. 67, #12, Dec. 1999, p. 1109. 
  • Sophie Bushwick, "Conquer Cold With DIY Hand Warmers", Popular Science, Vol. 286, #6, Dec. 2014, p. 79.
  • Theodore Gray, "Icy Hot", Popular Science, Vol. 279, #5, Oct. 2007, p. 80. 
  • Cy Tymony, "Cheap Gel Packs for Swollen Muscles", Sneaky Uses for Everyday Things, p. 7.
  • "Heat Packs. Item # 3227 Series Suggested Lesson Plans for Elementary, Middle, and High School", American Scientific.
  • Borislaw Bilash II, “Heat Me Up With Heat of Crystallization“, A Demo A Day – A Year of Physical Science Demonstrations, p. 63.
  • Borislaw Bilash II, “Crystal Heat Pack“, A Demo A Day – A Year of Physical Science Demonstrations, p. 170.


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